1. Field of the Invention
This invention relates to a liquid-absorbing article that has a porous outer fabric which surrounds an absorbent material that includes fine, fibrous polyolefin particles. More particularly, the invention concerns such an article in which the polyolefin particles are of flash-spun polyethylene and the absorbent material includes a wetting agent. The article of the invention exhibits particularly useful absorption characteristics for aqueous liquids, solvents and oils.
2. Description of the Prior Art
Liquid-absorbing articles in which ground corn cobs and chaff form an absorbent material within a porous, knitted or woven fabric which is closed at each end are known, for example from Stapelfeld et al, U.S. Pat. No. 4,659,478. Such articles, in which the ground corn cobs and chaff are replaced by melt-blown polypropylene microfibers, have been used commercially to absorb solvents, oils or aqueous spills from floors and to prevent spilled liquids from spreading. The articles also have been used on or at the base of machines, such as lathes, milling machines, cutters, metal-cleaning solvent baths, and the like. These machines employ liquids for cooling, cleaning or the like. The liquids are prone to splatter or spill in normal use. To be satisfactory for these uses, the liquid-absorbing article should be conformable to the surface on which it is placed and should be readily bendable so that one or more of such absorbing articles can be used to easily surround the liquid, form a dam and prevent spreading of the liquid on the surface. After the liquid-absorbing article has become full or saturated, it should not show a tendency for significant dripping when the article is lifted out of the liquid it is absorbing. The absence of dripping allows the article to be placed safely into a container for subsequent suitable disposal.
The above-described liquid-absorbing articles have been used with some success in industry. However, the utility of these liquid-absorbing articles could be considerably enhanced, if an absorbent of lighter weight could be made to absorb as much liquid as rapidly as the commercially used absorbers. Further, the commercial liquid-absorbing articles tend to compact on storage before use. Such compaction is undesirable; it apparently causes the article to become less absorbent and less conformable.
Other types of liquid-absorbing articles have been suggested for removing oils from water, as might be encountered in a water-polluting oil spill. For example, Wiegand et al, U.S. Pat. No. 4,070,287, discloses a sorbent material comprising a blend of 25-90% by weight of polymeric fibers of less than 40 microns in diameter and 5-75% cellulosic fibers formed into a bonded or nonbonded web or mat-like structure or merely blended and inserted into a fine mesh net-like enclosure. Ground polyethylene foams are also disclosed for the polymeric fibers. As another example, Schwartz et al, U.S. Pat. No. 4,052,306, discloses a floatable device for sweeping oil from the surface of a body of water. The device includes a netting that holds a web of melt-blown polymeric microfibers (preferably of less than 10 .mu.m in diameter) of polyolefin, polystyrene, polyester or polyamide. Although these articles might be helpful in clean-up of oil spills, such articles generally are inadequate for aqueous spills.
Accordingly, an object of this invention is to provide an improved liquid-absorbing article which is suitable for absorbing oily or aqueous liquids.